Dating aggression among youth involved with the juvenile justice system (JJS) is an area in great need of innovation. Not only because of the pernicious course of negative impacts on both adolescents and their partners, but also because of the intersection with issues ranging from custody to delinquency to trafficking. To date, knowledge in the field of violence prevention has been limited by reliance on traditional, self-report instruments that are not designed to capture risk factors for dating aggression with precision and in real-time. Furthermore, research has not caught up with the growing influence of online social networks (OSN) on relationship functioning. Thus, we will employ a novel combination of online social networking (OSN) data, ecological momentary assessment (EMA), computer-based, and interview methodologies to assess the phenomenology of dating aggression among JJS-involved youth. We will recruit a sample of 300 court-involved, non-incarcerated adolescents (ages 14-18) in current dating relationships from the Rhode Island Family Court. Adolescents will complete a baseline assessment and participate in laboratory tasks, followed by a four-week EMA protocol on their mobile devices. At 4-week follow-up, youth will return devices, permit download of OSN for the prior 4 weeks, as well as complete self-report assessments. Understanding the interplay of temporally linked daily assessments and conflictual interactions prior to and following dating aggression is crucial, both to document the phenomenology of these behaviors among JJS- involved youth and to lay the groundwork for future interventions that will be able to incorporate real-time user data with personalized feedback to offset the development of violent episodes in vivo. !